Deficits in both early and late stages of information processing have been widely reported in schizophrenia. Startle eye blink modification (SEM) has been shown to be a unique physiological tool for measuring events in these specific stages. A large literature has shown that schizophrenia patients exhibit performance deficits on continuous performance tests (CPTs) (i.e. tasks requiring attention to rapidly paced numbers, letters or shapes). Specific stages of information processing (early or late) during CPTs can be assessed using the SEM technique. Recent evidence suggests that nicotine intake and nicotine withdrawal effect early information processing as measured by SEM. The purpose of the proposed study is to extend the previous behavioral research measuring processing deficits in schizophrenia that utilized CPTs. Employing the SEM paradigm will allow the identification of the specific stages of attentional processing (early or late) which are deficient. Further, the SEM technique will allow for the measurement of the specific stages affected by nicotine withdrawal. The differences in the affect of nicotine in schizophrenia patient smokers versus nonsmokers and versus control smokers and nonsmokers will be measured during the CPT. [unreadable] [unreadable]